The invention is in the field of whirlpool bathtub jet apparatus.
Millions of whirlpool baths have been sold over the past thirty years and millions more will be installed in the near future. Whirlpool baths are used for recreational and medicinal purposes in homes, rehabilitation centers, and hospitals.
Conventional whirlpool baths pump water from the interior of the bathtub through generally inaccessible piping located on the outside of the bathtub. The water passing through the piping is forced back into the interior of the bathtub through nozzles on the interior side of the bathtub.
A major shortcoming of conventional whirlpool baths is the problem of complete drainage from the exterior piping of unsanitary bath residue, including soap scum, scale deposits, body oils and other body fluids, and fecal matter. Whirlpool bathtub piping is dark, warm, and moist, thus making it an excellent breeding ground for bacteria and fungi found in bath residue. There is considerable medical evidence linking whirlpool piping systems to infections in humans. See, e.g., "Characteristics of Pseudomonas Aeruginosa Isolated from Whirlpools and Bathers," Highsmith et al., Infection Control, 1985 Vol. 6 No. 10, pp. 407-412; "Fungi in Bathwater and Sludge of Bathroom Drain Pipes," Nishimura et al., Mycopathologia 97, 1987, pp. 17-23; "Hot Tub-Associated Dermatitis due to PA, Case Report and Review of the Literature," Chandrasekar et al., Archives of Dermatology, Vol. 120, October 1984; "PA Infections Associated with Hot Tubs and Other Environments," Gregory et al., New Challenges From Infectious Diseases, 081-5520/87 pp. 638-648; "Hot Tub Folliculitis," Jenkerson et al., Alaska Medicine, April-June 1987, pp. 51-53. Some of the foregoing whirlpool infections are deadly. For example, the reported overall mortality rate of PA pneumonia is approximately 70%.
To mitigate against the dangers of whirlpool infections, many manufactures recommend that the whirlpools be regularly drained and cleaned. However, no conventional whirlpool bathtub circulation system can be fully drained, and research has demonstrated that such circulations systems can be cleaned only with the use of expensive specialized equipment that will heat, convey, and concentrate special cleaning solutions through the bathtub piping. "Bacterial Hazards in Whirlpool Baths," Guimond, The ASHI Technical Journal, Spring 1993, p. 45. No cleaning solution can be adequately circulated through such piping simply by adding it to the bathtub and activating the whirlpool bathtub pump. Id. at 44.